Sergio Perez says McLaren will find it harder to score significant points during the remaining races of the season.

McLaren has yet to score a podium in 2013 having started well behind the development curve with its new car. However, with the team already focused on next season's new regulations, Perez has warned that the top four of Red Bull, Ferrari, Mercedes and Lotus are going to move further away from McLaren.

"Obviously, the fight at the sharp end of the championship means that the top three or four teams are still pushing hard to develop their current cars, whereas some of the others are looking more towards 2014," Perez said. "That means that it's getting slightly harder to score good points in the remaining races.

"However, we've still got developments coming through - most with an eye to next year - and I hope that we can maximise our package for one of the toughest races of the year."

Perez hopes that McLaren may be able to take advantage of a higher rate of attrition in Singapore.

"Singapore is an unpredictable race - it's tough on drivers and machinery, so we'll be looking to get the best from our high-downforce set-up and see if we have a car that can ride the circuit's many bumps. I like street circuits - you can really attack the corners - so I'm really looking forward to the whole weekend."